Process for making nitrogen oxids from air.



No. 884,919. I w PATENTED APR. 14, 1908.

' A. GRAU & F. RUSS. v

PROCESSTOR MAKING NITROGEN OXIDS FROM AIR.

v APPIIIUATION EILE'D. OUT. 8, 1907.

- INVENTORIS Jf' n; Rays ATTORNEY 'AUGUSTGRAU nn rnxNz Buss, or ienna,-AUsTRLA-HUNGARY.

PROCESS FOR MAKING NITROGEN OXIDS AIR.

I No. es4,eie.

Specification of Letters Patent; Application filed October 8, 1967-. Serial No. 396,488.\

, r Patented April 14, mos.

To all whom it may concern:

' tric arc.

- Be it known that we, Auous'r GRAU,P1O- fessor of'e'lectrical arts, and- FRANZ Russ, doctor oftechnical sciences, subjects ofthe Emperor of Austria-Hungary, residing at Vienna, Austria-Hun ary, have invented certam new and useiill Improvements in Processes for Making Nitrogen Oxids from vAir, of which the and oxygen, hereinafter referred to as air, is

. sible in order to from takingplace gases from t electric flame to the .tric arc is ractically instantaneous.

.groj ecting exposed the greater is the percentage of oxids of nitro en obtaiiied, and also that the reaction at t. e veryhigh temperaturesof the elec- When owever, are cooled down slowly dissociation of the oxide of nitrogen back again into oxythe gases,

gen and nitrogen takesplace and 'many methods have been suggested for cooling down the hot reaction gases as rapidly as posprevent such dissociation to any great extent. Now since the inner part of an electric arc is hotter than the outer zones, of the oxids of nitrogen is greater in the inner than in the outer zones.

Incarryin outside of the flame, and we do not permlt the gases to become partially dissociated by passing through the outer zones, and in, tlus wa our invention differs from the methods hit erto described. In order to take the gases substantially from the central zone of the flame we use a tube of into the .said inner zone of the ame an withdraw the gases through this tube. We also cool this tube, for instance by means of a wateror air-jacket, on the one hand to prevent the tubefrom melting and also to rapidly cool the gases being withdrawn down to a temperatureunder.1500

C. since the dissociation below this temperaosing a mixture ofis shown surrounded the concentration out our invention we draw the. e center or inner zone of the exclusion or substan-v tially-to the exclusion of the outer zone or.

small diameter ,ture is only very small. If desired, twoor more such tubes may be introduced into the flame, or one electrode itself may be hollow .andact as the tube through which the gases are withdrawn. that the electric prossible, otherwise gases 0th om the central zone will be drawn through the tube and'for this purpose it is preferred flame should be as steady as er than those It is of course preferable to make use of a perpendicularflame s'urrounded by a tube. If desired, this surroundin'g tube can be closed with the exception of in at and outlet pipes so that other mixtures of nitrogen and oxygen, for instance air, mixed with oxygen, can betreated in the flame.

The drawings accompanying this specificationwill help to illustrate further the nature of our invention, which however is not limit-' ed to the use of the a paratus shown therein. Figures 1, 2, 3, an 4 are all diagrammatic sections of ap flame is forms and how the gases'are withdrawn from the central zone. In Fig. 1 a,'b are electrodes, 0 zone and d are flame and e is the narrow tube through which the gases are withdrawn. 7 1 In Fig. 2, a, b are electrodes and the flame by a tube f,the air, or other mixture of oxygen and nitrogen, enters through h and the gases are withdrawn through two narrow tubes e, e, passin through openings g, g, in the side of the tube 4 and projecting into the central zone of the flame. Fig. 3 represents an a paratus in which the electrode a is hollow an serves as the narrow tube throughwhich the ases are withdrawn from. the central, zone, is the other electrode, f is the tube surroundin the flame, and h is the opening through w ich theair enters the tube f.

Fig. 4.represents a modification of the apparatus shown in Fig. 3 in which the tubef in which the flame is formed is surrounded by a wider tube '01.

to pass between enter. the tube f, the same time warming treated in the flame. In-this case also the ases are drawni'rom the central zone of the ame through the electrode a.

is the inner thus cooling the tube f and at the air which is to be the outer zones of the electric.

aratus showing where the I The air to be treated is made the tubes '5 and f and then to In this aisplieation We make no claim to theapparatus escribed and illustrated herein;

smce we desire to claim suchapparatus in another application of like date with the present set our hands 1n presence of two suhscnbmg 1 5 ap lication Serial No. 396,437. /'hat we claim is:

The process of making nitrogen oxiils from the air by flame and withdrawing the treated gases di- 10 rectly from the central zone of the electric flame-substantially to the exclusion of gases passing air into an electric arcfrom the outer zones and immediately coolin the said gases substantialllyq as described.

11 testimony whereof we wltnesses.

AUGUST GRAU. FRANZ RUSS.-

ave hereunto 

